import math
n=input()
sume=[]
for i in range(0,100):
    sume.append(0.0)
def f(x,y):
    for i in range(-5,5):
        for j in range(-5,5):
            sume[i+5][j+5]+=(y-i*x+j)**2
for i in range(0,n):
    t=raw_input().split(" ")
    t[0]=float(t[0])
    t[1]=float(t[1])
    f(t[0],t[1])
sume.sort()
print sume[0]